Date: Tue, 16 Aug 2016 17:14:07 -0700
From: Peter Todd <pete@petertodd.org>
To: Aiqin Li <liaiqin.lanzhou@gmail.com>,
	Bitcoin Protocol Discussion <bitcoin-dev@lists.linuxfoundation.org>
Message-ID: <20160817001407.GA6571@fedora-21-dvm>
References: <57B31EBC.1030806@jonasschnelli.ch>
	<0501f5c2-611c-53c1-5fd1-d4da5ba5137b@gmail.com>
MIME-Version: 1.0
Content-Type: multipart/signed; micalg=pgp-sha256;
	protocol="application/pgp-signature"; boundary="6TrnltStXW4iwmi0"
Content-Disposition: inline
In-Reply-To: <0501f5c2-611c-53c1-5fd1-d4da5ba5137b@gmail.com>
User-Agent: Mutt/1.5.23 (2014-03-12)
Subject: Re: [bitcoin-dev] Hardware Wallet Standard
Precedence: list


--6TrnltStXW4iwmi0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
Content-Transfer-Encoding: quoted-printable

On Wed, Aug 17, 2016 at 09:36:02AM +1000, Aiqin Li via bitcoin-dev wrote:
> Out of curiosity, what is the technical reason a normal ECC-enabled
> smart-card cannot be used for the hardware signing component of a wallet
> app? (Since if it can, its standardization must have been discussed.)
>=20
> Debian wiki gives a list of such cards with related opensource software to
> access them.

I'm not aware of any ECC-enabled smart-cards that can sign the specific cur=
ve
that Bitcoin uses, not to mention the fact that those smartcards generally =
only
speak higher level protocols than raw signature generation, precluding the
signing of bitcoin transactions.

The other serious problem - and this is a problem with smartcards in general
anyway - is that without Bitcoin-specific logic you're just signing blindly=
; we
recently saw the problems with that with the Bitfinex/BitGo hack. And even
then, without a screen most of the hardware wallets in are still just signi=
ng
blindly, with at best hard-to-use limits on maximum funds moved
per-transaction. Also note how even hardware wallets with a screen, like
Trezor, aren't yet able to authenticate who you are paying.

--=20
https://petertodd.org 'peter'[:-1]@petertodd.org

--6TrnltStXW4iwmi0
Content-Type: application/pgp-signature; name="signature.asc"
Content-Description: Digital signature

-----BEGIN PGP SIGNATURE-----

iQEcBAEBCAAGBQJXs6xNAAoJEGOZARBE6K+yNtUH/Rq3yQdaiGiGylRJg9L4r4AD
Pt6o5Svs/bD5yFYutcQkBP7O/u3JVCy+suK4s9gPRJ9ryzAY8Ca96HRfzP1AZZDt
NOpoDi9SyyuvymZoiM0uR3Z9SHGBkHTIdDFze4cG28hR2xsPAIYlneAKq9mxLtrZ
A6u1jGH38Ee+y5C5G+Ekj/L9/O/+I/kBlK9sYmLVsgRZAQCl6AZxtn9KO/ttjjhd
udUt9Eybx45kpxk2AE/QeLFttWdesYgqJUF5d3eveAupW7PI5s6VQIqZQNPCbF9+
g499A4T8NR0ntL4nD5uZviXzqqhtObqHy9uG1A2QOHqTJSHZIcaCrZTy177sXFI=
=1b6E
-----END PGP SIGNATURE-----

--6TrnltStXW4iwmi0--